25856839 has 2 divisors, whose sum is σ = 25856840. Its totient is φ = 25856838.

The previous prime is 25856827. The next prime is 25856843. The reversal of 25856839 is 93865852.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25856839 is a prime.

It is a super-2 number, since 2×25856839² = 1337152246143842, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25856869) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12928419 + 12928420.

It is an arithmetic number, because the mean of its divisors is an integer number (12928420).

Almost surely, 2^25856839 is an apocalyptic number.

25856839 is a deficient number, since it is larger than the sum of its proper divisors (1).

25856839 is an equidigital number, since it uses as much as digits as its factorization.

25856839 is an evil number, because the sum of its binary digits is even.

The product of its digits is 518400, while the sum is 46.

The square root of 25856839 is about 5084.9620450894. The cubic root of 25856839 is about 295.7048700367.

The spelling of 25856839 in words is "twenty-five million, eight hundred fifty-six thousand, eight hundred thirty-nine".